Performance Analysis of Random Fourier Features-Based Unsupervised Multistage-Clustering for VLC

Visible light communication (VLC) has emerged as a secure, cost-effective, and green supplement to the existing radio frequency (RF) communication systems. However, the performance of a typical VLC link is degraded by the following factors: (a) inter-symbol interference (ISI), which arises due to limited modulation bandwidth of light-emitting diode (LED), (b) the dispersion due to multi-path reflections, and (c) nonlinear transfer characteristics of LED. To mitigate ISI and LED nonlinearity, existing blind post-distorters, like the Volterra modified cascaded multimodulus algorithm (MCMMA) and the Hammerstein improved multistage clustering (HIMSC) approaches, experience degradations from modeling errors due to abrupt polynomial-series truncation. To mitigate these degradations, we propose a novel random Fourier features (RFF) based improved multi-stage clustering (RFF-IMSC) algorithm for blind post-distortion. Simulations performed over standardized IEEE 802.15 PAN VLC channels indicate that the proposed RFF-RIMSC post-distorter delivers improved performance as compared to the existing blind post-distorters. Also, analytical guarantees are presented and error-rate performance are analyzed for the $\epsilon $ -optimality of this approach with respect to supervised loss-functions.